2021 TOYOTA 4RUNNER change key battery

791-3. Theft deterrent system
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For safety and security
4RUNNER (U)
The alarm uses light and sound to give an alert when an intrusion is
detected.
The alarm is triggered in the following situations when the ala rm is
set:
● A locked door is unlocked or opened in any way other than using
the entry function, wireless remote control or mechanical key. (The
doors will lock aga in automatically.)
● The hood is opened.
● The battery is reconnected.
Close the doors and hood, and
lock all the doors. The system will
be set automatically after 30 sec-
onds.
The indicator light changes from
being on to flashing when the sys-
tem is set.
Do one of the following to deac tivate or stopping the alarms:
● Unlock the doors.
● Vehicles without a smart key sy stem: Turn the engine switch to
“ACC” or “ON” position, or start the engine. (The alarm will be deac-
tivated or stopped after a few seconds.)
● Vehicles with a smart key syst em: Turn the engine switch is in
ACCESSORY or IGNITION ON mode, or start the engine. (The
alarm will be deactivated or s topped after a few seconds.)
Alar m
: If equipped
The alarm
Setting the alarm system
Deactivating or stopping the alarm

1243-2. Opening, closing and locking the doors
4RUNNER (U)■
Note for the unlocking function
●Gripping the door handle when wearing a glove may not unlock th e door.
● A sudden approach to the effective range or door handle may prevent the
doors from being unlocked. In this case, return the door handle to the origi-
nal position and check that the doors unlock before pulling the door handle
again.
● If there is another electronic key in the detection area, it ma y take slightly
longer to unlock the doors after the door handle is gripped.
■ When the vehicle is not driven for extended periods
●To prevent theft of the vehicle, do not leave the electronic ke y within 6 ft. (2
m) of the vehicle.
● The smart key system can be deactivated in advance. Ask your To yota
dealer for details.
● Setting the electronic key to battery- saving mode helps to reduce key bat-
tery depletion. ( P. 121)
■ To operate the system properly
●Make sure to carry the electronic key when operating the system. Do not get
the electronic key too close to the vehicle when operating the system from
the outside of the vehicle.
● Depending on the position and holding condition of the electronic key, the
key may not be detected correctly and the system may not operat e properly.
(The alarm may go off accidentally, or the door lock prevention function may
not operate.)
■ If the smart key system does not operate properly
●Locking and unlocking the doors: Use the mechanical key. ( P. 507)
● Starting the engine: P. 508
■ Customization
Settings (e. g. operation signal) can be changed.
(Customizable features: P. 545)
■ If the smart key system has been d eactivated in a customized setting
● Locking and unlocking the doors: P. 507
● Starting the engine and changing engine switch modes: P. 508
● Stopping the engine: P. 213

2154-2. Driving procedures
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Driving
4RUNNER (U)■
If the engine does not start
●The engine immobilizer system may not have been deactivated. ( P. 76)
Contact your Toyota dealer.
● Check that the shift lever is securely set in P. The engine may not start if the
shift lever is displaced out of P.
■ Steering lock
After turning the engine switch off and opening and closing the doors, the
steering wheel will be locked due to the steering lock function. Operating the
engine switch again automatically cancels the steering lock.
■ When the steering lock cannot be released
■ Steering lock motor overheating prevention
To prevent the steering lock motor from overheating, the motor may be sus-
pended if the engine is turned on and off repeatedly in a short period of time.
In this case, refrain from operating the engine. After about 10 seconds, the
steering lock motor will resume functioning.
■ When a message requesting the smart key system be inspected is dis-
played on the multi-information display
The system may be malfunctioning. Have the vehicle inspected by your
Toyota dealer immediately.
■ If the electronic key battery is depleted
P. 443
■ Operation of the engine switch
If the switch is not pressed shortly and firmly, the engine swi tch mode may
not change or the engine may not start. When the steering lock cannot be
released, “Push the engine switch while
turning the steering wheel in either direc-
tion” will be displayed on the multi-infor-
mation display.
Press the engine switch shortly and firmly
while turning the steering wheel left and
right.

2294-3. Operating the lights and wipers
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Driving
4RUNNER (U)■
Automatic light off system (if equipped)
Vehicles without a smart key system
● When the headlights come on: The headlights and tail lights tur n off 30 sec-
onds after a door is opened and closed if the engine switch is turned to the
“ACC” or “LOCK” position. (The lights turn off immediately if on the
key is pressed after all the doors are locked.)
● When only the tail lights come on: The tail lights turn off automatically if the
engine switch is turned to the “ACC” or “LOCK” position and the driver’s
door is opened.
To turn the lights on again, turn the engine switch to the “ON” position, or turn
the lights off and then back to or .
Vehicles with a smart key system
● When the headlights come on: The headlights and tail lights tur n off 30 sec-
onds after a door is opened and closed if the engine switch is turned to
ACCESSORY mode or turned off. (The lights turn off immediately if
on the key is pressed after all the doors are locked.)
● When only the tail lights come on: The tail lights turn off automatically if the
engine switch is turned off and the driver’s door is opened.
To turn the lights on again, turn the engine switch to IGNITION ON mode, or
turn the light switch off and then back to or .
■ Customization
Settings (e.g. light sensor sensitivity) can be changed.
(Customizable features: P. 545)
NOTICE
■To prevent battery discharge
Do not leave the lights on longer than necessary when the engin e is not
running.

3996-2. Maintenance
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Maintenance and care
4RUNNER (U)■
Resetting the message indicating ma intenance is required (U.S.A. only)
After the required maintenance is performed according to the ma intenance
schedule, please reset the message.
To reset the message, follow the procedures described below:
Turn the engine switch off with the trip meter A reading shown. (P. 89)
Vehicles without a smart key system:
While pressing the display change button ( P. 89), turn the engine switch
to the “ON” position (do not start the engine because reset mod e will be
canceled).
Vehicles with a smart key system:
While pressing the display change button ( P. 89), turn the engine switch
to the IGNITION ON mode (do not start the engine because otherw ise the
reset mode will be canceled).
Continue to press and hold the button until the trip meter disp lays “000000”.
■ Allow inspection and repairs to be performed by a Toyota dealer
●Toyota technicians are well-trained specialists and are kept up to date with
the latest service information. They are well informed about th e operations
of all systems on your vehicle.
● Keep a copy of the repair order. It proves that the maintenance that has
been performed is under warranty coverage. If any problem should arise
while your vehicle is under warranty, your Toyota dealer will p romptly take
care of it.
WARNING
■ If your vehicle is no t properly maintained
Improper maintenance could result in serious damage to the vehi cle and
possible death or serious injury.
■ Handling of the battery
● Engine exhaust, some of its constituents, and a wide variety of automobile
components contain or emit chemicals known to the State of California to
cause cancer and birth defects and other reproductive harm. Wor k in a
well ventilated area.
● Oils, fuels and fluids contained in vehicles as well as waste produced by
component wear contain or emit chemicals known to the State of Califor-
nia to cause cancer and birth defects or other reproductive har m. Avoid
exposure and wash any affected area immediately.
● Battery posts, terminals and related accessories contain lead a nd lead
compounds which are known to cause brain damage. Wash your hand s
after handling. ( P. 417)
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5087-2. Steps to take in an emergency
4RUNNER (U)
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Toyota emblem side
of the electronic key to the
engine switch.
When the electronic key is
detected, a buzzer sounds and the
engine switch will turn to IGNITION
ON mode.
When the smart key system is
deactivated in customization set-
ting, the engine switch will turn to
ACCESSORY mode.
Firmly depress the brake pedal and check that is displayed
on the multi-information display.
Press the engine switch shortly and firmly.
In the event that the engine still cannot be started, contact your Toyota
dealer.
■ Stopping the engine
Shift the shift lever to P and press the engine switch as you normally do when
stopping the engine.
■ Replacing the key battery
As the above procedure is a temporary measure, it is recommende d that the
electronic key battery be replaced immediately when the battery is depleted.
( P. 444)
■ Changing engine switch modes
Within 10 seconds of the buzzer sounding, release the brake ped al and press
the engine switch.
The engine does not start and modes will be changed each time t he switch is
pressed.( P. 213)
■ When the electronic key does not work properly
●Make sure that the smart key system has not been deactivated in the cus-
tomization setting. If it is off, turn the function on.
(Customizable features: P. 545)
● Check if battery-saving mode is set. If it is set, cancel the f unction.
( P. 121)
Starting the engine
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